Backport: If tap_idle_timeout == 0, just wait "forever"
Backport: If tap_idle_timeout == 0, just wait "forever"

This is part of the fix for bug 1357.

It is a backport of
e6994f1f97f055b0e6efbddeb44c9a035c945d34
http://review.northscale.com:8080/#change,578

Change-Id: Iee46fd4ee1d77ddaa33d1a7f1918c4e93f55117e
Reviewed-on: http://review.northscale.com:8080/589
Reviewed-by: Dustin Sallings <1c08efb9b3965701be9d700d9a6f481f1ffec3ea@spy.net>
Tested-by: Dustin Sallings <1c08efb9b3965701be9d700d9a6f481f1ffec3ea@spy.net>

hisundar/ep-engine,daverigby/kv_engine,owendCB/ep-engine,couchbaselabs/ep-engine,couchbase/ep-engine,daverigby/ep-engine,couchbase/ep-engine,membase/ep-engine,membase/ep-engine,teligent-ru/ep-engine,owendCB/ep-engine,owendCB/ep-engine,couchbase/ep-engine,couchbaselabs/ep-engine,teligent-ru/ep-engine,daverigby/ep-engine,teligent-ru/ep-engine,sriganes/ep-engine,abhinavdangeti/ep-engine,jimwwalker/ep-engine,daverigby/kv_engine,zbase/ep-engine,sriganes/ep-engine,zbase/ep-engine,abhinavdangeti/ep-engine,daverigby/ep-engine,jimwwalker/ep-engine,zbase/ep-engine,abhinavdangeti/ep-engine,hisundar/ep-engine,jimwwalker/ep-engine,couchbaselabs/ep-engine,zbase/ep-engine,hisundar/ep-engine,sriganes/ep-engine,couchbaselabs/ep-engine,jimwwalker/ep-engine,couchbase/ep-engine,daverigby/kv_engine,abhinavdangeti/ep-engine,sriganes/ep-engine,membase/ep-engine,zbase/ep-engine,daverigby/ep-engine,abhinavdangeti/ep-engine,daverigby/kv_engine,membase/ep-engine,owendCB/ep-engine,teligent-ru/ep-engine,couchbaselabs/ep-engine,hisundar/ep-engine